engine and drivetrain More Weber 32/36 Questions

[glemon]

I was reading the current Weber 32/36 thread with interest as I too think my car is running rich, but since my questions are a little different thought I would start my own topic. Weber carbs and the various jets and all that are still very much a mystery to me, so I will limit my questions to what I can observe at this point.

Starting, when I first got the car starting from cold and sitting a while took quite a bit of cranking. In my first partial tear down and inspection of the carb I discovered the choke linkage had come adrift and was not closing the top butterfly as it should. Now it fires first try, but it will not stay running, I have to fiddle with the gas pedal as well, and it is very finicky, too much gas too fast and it dies, so a cold start is usually numerous tries before it catches for good. Anyway, it appears the choke linkage is now doing it's thing correctly on choke, but not giving it much throttle to go with the choke, is there any way to adjust this, that being said it appears to be adjusted fairly well, but between all the items that get you here to there from the choke cable to the throttle there is a little play in each and it turns into a lot of play by the time you get to the throttle, so maybe that is the nature of the beast, but I would think with proper choke and a little more throttle it would start and stay going (if I turn up the idle screw so that it idles at about 1500 when warm it stays running cold, but then of course it will still idle at 1500 warm, so I am thinking a little more throttle from the choke is what I need, but I am not sure how to adjust it.

Running, the car runs well once I get past the original starting issue, but I think it is running a little rich, it also seems to use a LOT of gas, one thing I noticed is that the accelerator pump (think that is the right term) really squirts a lot of fuel into the motor when I hit the accelerator, so much that gas is pooling on the throttle butterfly on the bottom of the carb, but Weber carbs are new to me, is this normal? Thanks, Greg

[TobyB]

There IS a screw that adjusts the 'idle up' lever- and yes, they wear, so that eventually the carb doesn't fuel enough

for as much 'strangle' (French word for it) as it gets.  Turn that screw in 1/2 turn increments, though-

since it wears to the curve of the cam, it's nonlinear in its response.  Where is it?  I forget, but if you have

someone pull the choke while you're looking, you'll find it.  Pic, anyone?

 

As to running rich, start with the basics- is your float full of gas, is your float level set right, IS YOUR FLOAT VALVE SEALING

(that's one we haven't been plugging recently, but it's possible for the little suckers to leak just a bit, and you get a rich

idle and slow acceleration, but fine 'on throttle' response)

and has it been 'rebuilt' in the last few years?  By rebuilt, I really mean cleaned out and had a new rubber kit put into it.

The power valve diaphragm stiffens with age (exactly the opposite of... but I digress) and its operation is

pretty critical to the way the carb behaves...

 

hth

 

t

[c.d.iesel]

there's a seperate choke "HIGH IDLE" adjustment screw - it's not the same

idle adjustment screw

 

you adjust the HIGH IDLE screw with motor cold,

choke flap closed and the choke lever up on the

high step of the choke cam. Adjust for 1800 - 2200

rpm after the cold motor is started. As the motor and coolent and Bi-metalic

heating spring inside the choke cover warms up - the choke rod

will come off the HIGH STEP of the cam and rest on the second

step, HIGH idle lowers a bit, and after approx 3 - 4 min running

and warming up the choke rod comes off any steps of the cam and

now your idle speed is controled by the idle screw acting

on the carb's lower throttle plate.

 

Ignition timing is IMPORTANT to set with a light correctly,

warm idle speed and warm idle mixture correct before the

cold choke settings can be reached

[TobyB]

That's true for an automatic choke- for a manual, it's a smooth cam.

 

t

 

edit- one more reason not to try to convert an auto choke to manual with one of those kits...

Edited October 2, 2013 by TobyB

[glemon]

Thanks guys I couldn't get to the car tonight, but have some things to try when I do. I got a new set of points, will put them on and check timing in the next couple of days. Greg